EP0727752B1 - Electronic identification system - Google Patents

Electronic identification system Download PDF

Info

Publication number
EP0727752B1
EP0727752B1 EP19950309390 EP95309390A EP0727752B1 EP 0727752 B1 EP0727752 B1 EP 0727752B1 EP 19950309390 EP19950309390 EP 19950309390 EP 95309390 A EP95309390 A EP 95309390A EP 0727752 B1 EP0727752 B1 EP 0727752B1
Authority
EP
European Patent Office
Prior art keywords
transponder
mode
interrogator
signal
response signal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP19950309390
Other languages
German (de)
French (fr)
Other versions
EP0727752A2 (en
EP0727752A3 (en
Inventor
Edwin Turner
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujitsu Services Ltd
Original Assignee
Fujitsu Services Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to GB9502907 priority Critical
Priority to GBGB9502907.0A priority patent/GB9502907D0/en
Application filed by Fujitsu Services Ltd filed Critical Fujitsu Services Ltd
Publication of EP0727752A2 publication Critical patent/EP0727752A2/en
Publication of EP0727752A3 publication Critical patent/EP0727752A3/en
Application granted granted Critical
Publication of EP0727752B1 publication Critical patent/EP0727752B1/en
Anticipated expiration legal-status Critical
Application status is Expired - Lifetime legal-status Critical

Links

Images

Classifications

    • GPHYSICS
    • G06COMPUTING; CALCULATING; COUNTING
    • G06KRECOGNITION OF DATA; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/10Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
    • G06K7/10009Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
    • G06K7/10019Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers.
    • G06K7/10029Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers. the collision being resolved in the time domain, e.g. using binary tree search or RFID responses allocated to a random time slot
    • G06K7/10059Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers. the collision being resolved in the time domain, e.g. using binary tree search or RFID responses allocated to a random time slot transponder driven
    • GPHYSICS
    • G06COMPUTING; CALCULATING; COUNTING
    • G06KRECOGNITION OF DATA; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/0008General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer

Description

    Background to the Invention
  • This invention relates to an electronic identification system comprising a plurality of transponders, and an interrogator for interrogating the transponders to obtain information stored in the transponders. The invention also relates to a transponder for use in such an identification system. The invention is particularly, although not exclusively, concerned with an electronic identification system using radio frequency (RF) technology for communication between the interrogator and the transponders.
  • Such an electronic identification system is described for example in European Patent Applications EP 0494114, EP 0585132 and EP 0598624, and in PCT Patent Application WO 93/17404.
  • Such systems have many potential applications, such as tagging goods, mail, vehicles or animals. For example, such a system could be used in a retail store to identify goods presented by a customer at a checkout. The transponders could be incorporated in tags attached to the goods or to their packaging.
  • In such a retail application, in order to detect unauthorised removal of goods from the store, an anti-theft gate may be positioned at the store exit, to detect the presence of transponders. It has been proposed in the above mentioned EP 0585132 to disable a transponder for a predetermined period of time (e.g. 10 minutes) after it has been successfully read at the checkout. This ensures that goods that have been paid for do not trigger the anti-theft gate, provided the customer leaves the store within the predetermined period. However, a problem with this is that if the customer later brings the purchased goods back into the store with the transponder still attached, the anti-theft gate will be triggered.
  • The above-mentioned WO 93/17404 proposes to write information into the transponder at the checkout, to indicate whether the article has been paid for or its removal has otherwise been authorised. This information can then be read at the anti-theft gate, so as to ensure that the anti-theft gate is not triggered by articles that are being legitimately removed from the store, or subsequently brought back into the store. However, a problem with this proposal is that it requires a relatively sophisticated anti-theft gate, capable not only of detecting the presence of a transponder, but also of interrogating it to read the information indicating whether the article has been paid for.
  • One object of the invention is to provide a novel electronic identification system which is capable of overcoming these problems.
  • According to one aspect of the invention there is provided an identification system as claimed in the appended claim 1.
  • According to another aspect of the invention there is provided transponder for use in an identification system as claimed in the appended claim 6.
  • Brief Description of the Drawings
  • Figure 1 is a schematic diagram showing an electronic identification system in accordance with the invention.
  • Figure 2 is a block diagram of an interrogator.
  • Figure 3 is a flow chart showing the operation of the interrogator.
  • Figure 4 is a block diagram of a transponder.
  • Figure 5 is a flow chart showing the operation of the transponder.
  • Description of an Embodiment of the Invention
  • One embodiment of the invention will now be described by way of example with reference to the accompanying drawings.
  • Referring to Figure 1, this shows an electronic identification system comprising an interrogator 10 and a plurality of transponders 11. The transponders may, for example, be incorporated into tags or labels attached to goods in a retail store, while the interrogator may be built into a checkout station in the store. The interrogator is connected to a host computer 12.
  • Referring to Figure 2, this shows the interrogator in more detail. The interrogator comprises an RF antenna 20, a transmitter circuit 21, a receiver circuit 22, and a controlling microprocessor 23. The antenna 20 is connected to both the transmitter and receiver circuits, and serves both for transmission and reception. The transmitter circuit is controlled by the microprocessor and, when powered up, generates an interrogation signal, comprising a continuous RF carrier signal.
  • As will be described, any transponders that detect the interrogation signal return a response signal, comprising an RF carrier signal modulated with coded data. The response signal is received by the antenna 20, and passed to the receiver circuit 22. The receiver circuit demodulates the response signal, by mixing it with an RF reference signal derived from the transmitter circuit, and passes the demodulated signal to the microprocessor 23 for decoding. The decoded data is then passed to the host computer 12. When the host computer detects that all the transponders have responded (e.g. because a time-out period has expired with no further responses) the host computer sends an END signal to the microprocessor.
  • Figure 3 shows a flowchart of the operation of the microprocessor 23. Initially, the microprocessor powers up the transmitter (step 30), so as to start transmitting the interrogation signal. The microprocessor then enters a loop in which it checks whether the END signal is present (step 31) and whether a response signal has been received from a transponder (step 32). When a response is received, the microprocessor decodes it, and performs a redundancy check to check whether the response is valid (step 33). If the response is not valid (e.g. because two transponders have returned responses simultaneously, so that their responses interfere with each other), the response is ignored and the microprocessor returns to await another response. When a valid response is detected, the microprocessor outputs the decoded data to the host computer and instructs the transmitter to send an ACK signal (step 34). The ACK signal consists of an interruption to the interrogation signal for one clock period, and serves as an acknowledgement to the transponder that its response has been correctly received. The microprocessor then loops back to step 31 to await the next response.
  • The microprocessor repeats this process until an END signal is received from the host computer at step 31, indicating that responses have been received from all the transponders. It then checks whether or not mode switching is enabled in the interrogator (step 35). If so, a SWITCH signal is sent (step 36). This signal consists of an interruption of the RF carrier for two clock periods, and hence is distinguished from the ACK signal. As will be described, the SWITCH signal switches the mode of each transponder that receives it. If mode switching is not enabled, no SWITCH signal is sent. Finally, the transmitter is powered down (step 37).
  • Referring now to Figure 4, this shows one of the transponders in more detail. The transponder comprises an antenna 40, a power supply 41, a code generator 42, a modulator 43, a variable attenuator 44, gap detection logic 45, a clock circuit 46, and a mode control bit 47. The antenna 40 serves for both transmission and reception and may, for example, comprise a printed conductive pattern. The power supply 41 comprises a diode, which rectifies the received RF signal and charges a capacitor. Thus, the transponder derives all its power from the incoming RF signal, and does not require any internal power source. The power supply provides power for the code generator, clock circuit and gap detection logic. The code generator 42 generates a coded signal which represents the information stored in the transponder, such as an identity code. The modulator 43 modulates this coded signal on to the carrier wave received from the antenna, and feeds this modulated carrier by way of the attenuator 44 to the antenna 40, for transmission as a response signal. The gap detection logic 45 detects both ACK signals and SWITCH signals.
  • The mode control bit 47 is stored in a non-volatile memory, so that it is preserved even when the transponder is powered down. (The non-volatile memory may be of the type which can be re-written, or may be of the type which, once written to, cannot be re-written). The mode control bit controls the variable attenuator 44, such that when this bit is set, the attenuator reduces the power level of the response signal from its normal level to a lower level. In other words, the transponder has two modes: a normal power mode and a reduced power mode. In the normal power mode, the signal level is such that it can be detected by the interrogator from a range of up to 2 metres. In the reduced power mode, on the other hand, the signal level is such that it can be detected only from a range of 10 centimetres or less.
  • Figure 5 is a flowchart showing the operation of the transponder. The code generator is powered up whenever an interrogation signal is received from the interrogator (step 50). When powered up, the code generator starts an internal counter, which generates a preset delay period (step 51). This delay period is chosen at random for each transponder so that, in general, each transponder has a different delay. The transponder then enters a loop (step 52) in which it waits for this delay period to expire. When the delay period expires, the code generator sends its stored code sequence to the modulator for transmission as a response to the interrogation signal (step 53).
  • The transponder then waits for a predetermined number of clock periods, and then checks whether an ACK has been detected (step 54). If no ACK is detected at the appropriate time, this indicates that the response has not been correctly received by the interrogator, probably because of interference with another transponder. In this case, the transponder returns to step 51, restarting the delay period, and the response is retransmitted after the delay expires. It can be seen that, if the delay periods of the two interfering transponders are different, they will retransmit at different times, and so avoid interference.
  • When an ACK is detected, code generation is disabled (step 55), so that no further responses are sent. The transponder then enters a loop (step 56), waiting for a SWITCH signal. When a SWITCH is received, the transponder sets the mode control bit (step 57) and then enters an idle loop (step 58), in which it remains until power is removed. If, however, the transponder is powered down before any SWITCH signal is received, the mode control bit remains unset.
  • A typical application of the identification system described above is in a retail store. Each item for sale in the store has a label, containing a transponder as described above. Each transponder is programmed with an identity code, uniquely identifying the item, and initially all of these transponders are in the normal power mode, i.e. their mode control bits are all unset. When a customer wishes to purchase one or more items, the customer passes the items through a checkout station which contains an interrogator as described above. The interrogator interrogates the transponders, so as to obtain their identity codes, and passes these codes to a point-of-sale computer for pricing. After all the transponders have been interrogated the interrogator sends a SWITCH signal. This switches all the transponders into the reduced power mode by setting their mode control bits. The checkout station may also write information into the transponders, if desired, such as the date of purchase.
  • The store has one or more anti-theft gates, positioned at the store exits. Each of these gates contains an interrogator, which interrogates any transponders that pass it. The anti-theft gate is designed so that it is impossible to bring any transponder closer than about 15 centimetres to the antenna of the interrogator. This means that any transponder in the reduced power mode will not be detected by the anti-theft gate, because its signal power level is insufficient to be detected over a range greater than 10 centimetres. However, any transponder still in the normal power mode will be detected, and this will trigger an audible or visible alarm.
  • In summary, it can be seen that when goods are taken through the checkout, their transponders are modified so as to reduce their signal power levels. This ensures that the goods will not erroneously trigger the anti-theft gate when they are taken out of the store, or if they are subsequently brought back into the store (e.g. as an item of clothing worn by the customer). However, it is still possible to interrogate the transponders if required, using equipment that can accept the reduced signal power level. For example, a customer services desk in the store may contain an interrogator, positioned immediately under the counter so that transponders may be brought very close to the interrogator's antenna. Such an interrogator would therefore be able to read the transponders of articles that had been purchased and returned for exchange or refund.
  • If the non-volatile memory which stores the mode control bit is of the re-writable type, then it is possible for to reset the mode control bit to its initial state, so as to restore the transponder to its normal power mode. This could be done for example if the article is to be put back on the shelves for re-sale.
  • It will be appreciated that while the embodiment of the invention described above relates to a retail environment, the invention may be used in many different applications.

Claims (8)

  1. An identification system comprising at least one interrogator (10) and a plurality of transponders (11), each transponder including means (42, 43, 40) for responding to an interrogation signal from the interrogator by returning a response signal to the interrogator,
    characterised in that each transponder (10) includes:
    (a) a non-volatile memory (47) for storing an indication of whether the transponder is in a first mode or a second mode;
    (b) mode control means (45) for setting the non-volatile memory (47) so as to switch the transponder from the first mode to the second mode in reponse to a mode switching signal; and
    (c) level control means (44) responsive to the non-volatile memory (47) for setting said response signal to a first power level when the transponder is in said first mode, and to a second, lower power level when the transponder is in said second mode.
  2. A system according to claim 1 wherein the level control means comprises a variable attenuator (44).
  3. A system according to Claim 1 or 2 wherein said interrogation signal, said mode switching signal, and said response signal are all radio frequency (RF) signals.
  4. A system according to any preceding claim wherein said interrogator (10) comprises means for generating said mode switching signal when a response signal has been received from each of said transponders (11).
  5. A system according to any preceding claim when used in a retail store, the system including:
    (a) a first interrogator (10) located in a checkout station in the store, and including means for generating said mode switching signal;
    (b) a second interrogator (10) located at an anti-theft gate in the store, said second interrogator being capable of detecting said response signal at said first power level but incapable of detecting said response signal at said second power level; and
    (c) a third interrogator (10) located at a service station, said third interrogator being capable of detecting said response signal at said second power level as well as at said first power level.
  6. A transponder (11) for use in an identification system, the transponder including means (42, 43, 40) for responding to an interrogation signal by transmitting a response signal containing information stored in the transponder,
    characterised by :
    (a) a non-volatile memory (47) for storing an indication of whether the transponder is in a first mode or a second mode;
    (b) mode control means (45) for setting the non-volatile memory (47) so as to switch the transponder from the first mode to the second mode in reponse to receipt of a mode switching signal; and
    (c) level control means (44) responsive to the non-volatile memory (47) for setting said response signal to a first power level when the transponder is in said first mode, and to a second, lower power level when the transponder is in said second mode.
  7. A transponder according to claim 6 wherein said level control means includes a variable attenuator (44).
  8. A transponder according to claim 6 or 7 wherein said interrogation signal, said mode switching signal, and said response signal are all radio frequency (RF) signals.
EP19950309390 1995-02-15 1995-12-22 Electronic identification system Expired - Lifetime EP0727752B1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB9502907 1995-02-15
GBGB9502907.0A GB9502907D0 (en) 1995-02-15 1995-02-15 Electronic identification system

Publications (3)

Publication Number Publication Date
EP0727752A2 EP0727752A2 (en) 1996-08-21
EP0727752A3 EP0727752A3 (en) 1997-05-28
EP0727752B1 true EP0727752B1 (en) 2002-09-18

Family

ID=10769603

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19950309390 Expired - Lifetime EP0727752B1 (en) 1995-02-15 1995-12-22 Electronic identification system

Country Status (7)

Country Link
US (1) US6549119B1 (en)
EP (1) EP0727752B1 (en)
JP (1) JP3795121B2 (en)
AU (1) AU696800B2 (en)
DE (2) DE69528246T2 (en)
GB (1) GB9502907D0 (en)
ZA (1) ZA9600264B (en)

Families Citing this family (67)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AUPO085596A0 (en) * 1996-07-05 1996-07-25 Integrated Silicon Design Pty Ltd Presence and data labels
AU737367B2 (en) * 1997-01-17 2001-08-16 Integrated Silicon Design Pty Ltd Multiple tag reading system
US6538564B1 (en) 1997-01-17 2003-03-25 Integrated Silicon Design Pty Ltd Multiple tag reading system
KR100607383B1 (en) * 1997-08-12 2006-08-02 코닌클리케 필립스 일렉트로닉스 엔.브이. Transponder for transmitting processed data to a base station over large distances and at a high data transfer rate
KR20010001221A (en) * 1999-06-02 2001-01-05 송길섭 Preventing apparatus and method for stolen of portable computer
CN1222900C (en) 1999-08-09 2005-10-12 第一数据公司 Point of sale payment terminal
US7600673B2 (en) * 1999-08-09 2009-10-13 First Data Corporation Systems and methods for performing transactions at a point-of-sale
GB0004456D0 (en) 2000-02-26 2000-04-19 Glaxo Group Ltd Medicament dispenser
NL1014540C2 (en) * 2000-03-02 2001-09-04 Nedap Nv Library System with electronic identification and locking of compact discs.
GB0012465D0 (en) 2000-05-24 2000-07-12 Glaxo Group Ltd Monitoring method
GB0013619D0 (en) 2000-06-06 2000-07-26 Glaxo Group Ltd Sample container
US7376587B1 (en) * 2000-07-11 2008-05-20 Western Union Financial Services, Inc. Method for enabling transfer of funds through a computer network
US8374962B2 (en) * 2001-10-26 2013-02-12 First Data Corporation Stored value payouts
US7398252B2 (en) * 2000-07-11 2008-07-08 First Data Corporation Automated group payment
US20020152168A1 (en) * 2000-07-11 2002-10-17 First Data Corporation Automated transfer with stored value fund
US8244632B2 (en) 2001-10-26 2012-08-14 First Data Corporation Automated transfer with stored value
EP1312012A4 (en) * 2000-07-11 2006-09-06 First Data Corp Wide area network person-to-person payment
EP1301230A1 (en) 2000-07-15 2003-04-16 Glaxo Group Limited Medicament dispenser
US7130817B2 (en) * 2000-12-15 2006-10-31 First Data Corporation Electronic gift linking
US7266533B2 (en) * 2000-12-15 2007-09-04 The Western Union Company Electronic gift greeting
US7165052B2 (en) * 2001-03-31 2007-01-16 First Data Corporation Payment service method and system
US7117183B2 (en) * 2001-03-31 2006-10-03 First Data Coroporation Airline ticket payment and reservation system and methods
US8150763B2 (en) * 2001-03-31 2012-04-03 The Western Union Company Systems and methods for staging transactions, payments and collections
WO2002079939A2 (en) * 2001-03-31 2002-10-10 First Data Corporation Electronic identifier payment system and methods
US9853759B1 (en) 2001-03-31 2017-12-26 First Data Corporation Staged transaction system for mobile commerce
US7184989B2 (en) * 2001-03-31 2007-02-27 First Data Corporation Staged transactions systems and methods
JP3927378B2 (en) * 2001-05-22 2007-06-06 株式会社日立製作所 Article management system using interrogator
US7706765B2 (en) * 2001-10-17 2010-04-27 Motorola, Inc. Method and device for enabling and disabling group transmissions
US6670569B2 (en) * 2001-11-08 2003-12-30 First Data Corporation Mail handling equipment and methods
US7050395B1 (en) * 2001-11-30 2006-05-23 Redback Networks Inc. Method and apparatus for disabling an interface between network element data processing units
SG124239A1 (en) * 2002-01-23 2006-08-30 Singapore Tech Aerospace Ltd Close proximity weapon id system
US7596529B2 (en) * 2002-02-13 2009-09-29 First Data Corporation Buttons for person to person payments
US20040006537A1 (en) * 2002-03-04 2004-01-08 First Data Corporation Method and system for processing credit card related transactions
FR2839574B1 (en) * 2002-05-10 2006-06-23 Radio Systemes Ingenierie Unit for recognizing a badge or the like and method using such a unit
US6989762B2 (en) * 2002-10-23 2006-01-24 Acco Brands, Inc. Proximity-based automatic ID code reconfiguration of wireless input/output systems
JP4337383B2 (en) * 2003-04-10 2009-09-30 セイコーエプソン株式会社 Equipment capable of mounting consumable containers
US7063473B2 (en) * 2003-04-18 2006-06-20 Canon Kabushiki Kaisha Both-side recording apparatus
US7831519B2 (en) * 2003-12-17 2010-11-09 First Data Corporation Methods and systems for electromagnetic initiation of secure transactions
US7219832B2 (en) * 2004-06-17 2007-05-22 First Data Corporation ATM machine and methods with currency conversion capabilities
US7917395B2 (en) 2004-09-28 2011-03-29 The Western Union Company Wireless network access prepayment systems and methods
US8152054B2 (en) 2004-10-19 2012-04-10 The Western Union Company Money transfer systems and methods
US7813982B2 (en) * 2004-11-08 2010-10-12 First Data Corporation Unit-based prepaid presentation instrument accounts and methods
US7248164B2 (en) * 2005-02-07 2007-07-24 Regard Joseph T Radio frequency identification bag tracking and recycling system, and bag counting rack associated therewith
US7474211B2 (en) * 2005-02-22 2009-01-06 Bradley Allen Kramer System and method for killing a RFID tag
US20070214091A1 (en) * 2005-05-18 2007-09-13 The Western Union Company Electronic payment instrument system and method
US7392940B2 (en) * 2005-05-18 2008-07-01 The Western Union Company In-lane money transfer systems and methods
WO2006134563A2 (en) 2005-06-14 2006-12-21 Nxp B.V. Transponder system for transmitting key-encrypted information and associated keys
WO2007008102A1 (en) * 2005-07-05 2007-01-18 Sergey Aleksandrovich Mosienko Identification data reader, used with identity papers or visas, and its embodiments
WO2007004916A1 (en) * 2005-07-05 2007-01-11 Sergey Aleksandrovich Mosienko Device for storing and transmitting identification data
US8672220B2 (en) 2005-09-30 2014-03-18 The Western Union Company Money transfer system and method
US8345931B2 (en) 2006-02-10 2013-01-01 The Western Union Company Biometric based authorization systems for electronic fund transfers
US20070273481A1 (en) * 2006-05-25 2007-11-29 Symbol Technologies, Inc. RFID tag with programmable read range
US7551080B2 (en) 2006-07-17 2009-06-23 Sensormatic Electronics Corporation Control for embedded and door-mounted antennas
US7933835B2 (en) 2007-01-17 2011-04-26 The Western Union Company Secure money transfer systems and methods using biometric keys associated therewith
US8818904B2 (en) 2007-01-17 2014-08-26 The Western Union Company Generation systems and methods for transaction identifiers having biometric keys associated therewith
US8504473B2 (en) 2007-03-28 2013-08-06 The Western Union Company Money transfer system and messaging system
US7783571B2 (en) 2007-05-31 2010-08-24 First Data Corporation ATM system for receiving cash deposits from non-networked clients
US8237546B2 (en) * 2007-06-28 2012-08-07 Symbol Technologies, Inc. Backscatter limited tags
US8565723B2 (en) * 2007-10-17 2013-10-22 First Data Corporation Onetime passwords for mobile wallets
US8095113B2 (en) * 2007-10-17 2012-01-10 First Data Corporation Onetime passwords for smart chip cards
US8552841B2 (en) * 2008-05-07 2013-10-08 Infineon Technologies Ag Communication method having selectable response signal strength levels
US20100048226A1 (en) * 2008-08-20 2010-02-25 First Data Corporation Managing mobile marketing offers
US8346611B2 (en) * 2009-04-21 2013-01-01 First Data Corporation Systems and methods for pre-paid futures procurement
RU2497147C2 (en) * 2011-11-18 2013-10-27 Открытое акционерное общество "Авангард" Method for detection and identification of desired transponders from plurality of passive transponders and system for implementing said method
US9822927B2 (en) * 2013-01-09 2017-11-21 Frederick Energy Products, Llc Mechanized area controller
CN104123514A (en) * 2013-04-26 2014-10-29 腾讯科技(深圳)有限公司 Shutdown validation method and device
US9578469B2 (en) 2014-10-02 2017-02-21 Motorola Solutions, Inc. Method and system for direct mode communication within a talkgroup

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4512033A (en) * 1982-11-29 1985-04-16 C-Cor Labs, Inc. Remote level adjustment system for use in a multi-terminal communications system
WO1987004282A1 (en) * 1986-01-03 1987-07-16 Advanced Systems Research Pty. Ltd. Inventory control system
NL8802718A (en) * 1988-11-04 1990-06-01 Nedap Nv The sequentially read-out of a plurality of radio-frequency detection label in an interrogation field.
JP2527267B2 (en) * 1990-04-19 1996-08-21 三菱電機株式会社 Non-contact type Allowed 搬担 body
AT313134T (en) * 1991-04-03 2005-12-15 Tagsys Sa Article sorting system
US5239167A (en) * 1991-04-30 1993-08-24 Ludwig Kipp Checkout system
NL9101608A (en) * 1991-09-24 1993-04-16 Nedap Nv Chip card with means of identification from a distance.
US5241923A (en) * 1992-07-23 1993-09-07 Pole/Zero Corporation Transponder control of animal whereabouts
FR2706934B1 (en) * 1993-06-21 1995-10-13 Valeo Electronique
US5517194A (en) * 1994-02-10 1996-05-14 Racom Systems, Inc. Passive RF transponder and method
US5602535A (en) * 1994-07-15 1997-02-11 The Friedkin Corporation Vehicle security system based on two step communication range between transmitter and receiver

Also Published As

Publication number Publication date
GB9502907D0 (en) 1995-04-05
JP3795121B2 (en) 2006-07-12
DE69528246T2 (en) 2003-05-15
EP0727752A3 (en) 1997-05-28
AU4552396A (en) 1996-08-22
ZA9600264B (en) 1996-08-01
DE69528246D1 (en) 2002-10-24
AU696800B2 (en) 1998-09-17
EP0727752A2 (en) 1996-08-21
JPH08249552A (en) 1996-09-27
US6549119B1 (en) 2003-04-15

Similar Documents

Publication Publication Date Title
US5519381A (en) Detection of multiple articles
ES2198938T3 (en) Application for a radio frequency identification system.
US7705712B2 (en) Smart card receiver and system for pulsed RF fields
US6354493B1 (en) System and method for finding a specific RFID tagged article located in a plurality of RFID tagged articles
EP1683122B1 (en) System for detecting radio-frequency identification tags
ES2434038T3 (en) Techniques for reducing false alarms, disabling invalid security and internal theft
JP3045774B2 (en) Transponder for the proximity identification system
US5602538A (en) Apparatus and method for identifying multiple transponders
EP0983692B1 (en) Cloaking circuit for use in radio frequency identification tags and method of cloaking rfid tags to increase interrogation reliability
US5942987A (en) Radio frequency identification system with write broadcast capability
AU721551B2 (en) A data communication and electronic article surveillance tag
ES2207833T3 (en) Improved identification system.
JP2974993B2 (en) Radio frequency identification tag
US5266925A (en) Electronic identification tag interrogation method
US6362738B1 (en) Reader for use in a radio frequency identification system and method thereof
JP2005528815A (en) Method and apparatus for identification
US20040046642A1 (en) Protocol for addressing groups of RFID tags
US20080210756A1 (en) Customer interaction with inventory via rfid
US6405102B1 (en) RF-interrogatable processing system
US8384519B2 (en) Reader device for radio frequency identification transponder with transponder functionality
US5625341A (en) Multi-bit EAS marker powered by interrogation signal in the eight MHz band
US6995655B2 (en) Method of simultaneously reading multiple radio frequency tags, RF tags, and RF reader
EP1076888B1 (en) Rfid tagging system for network assets
US7411503B2 (en) System and method for disabling data on radio frequency identification tags
JP4578139B2 (en) Information processing apparatus, program, storage medium, and method for receiving predetermined information

Legal Events

Date Code Title Description
AK Designated contracting states:

Kind code of ref document: A2

Designated state(s): DE FR GB IT NL

RHK1 Main classification (correction)

Ipc: G06K 19/07

AK Designated contracting states:

Kind code of ref document: A3

Designated state(s): DE FR GB IT NL

17P Request for examination filed

Effective date: 19971011

17Q First examination report

Effective date: 20011220

RAP1 Transfer of rights of an ep published application

Owner name: FUJITSU SERVICES LIMITED

AK Designated contracting states:

Kind code of ref document: B1

Designated state(s): DE FR GB IT NL

PG25 Lapsed in a contracting state announced via postgrant inform. from nat. office to epo

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20020918

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20020918

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REF Corresponds to:

Ref document number: 69528246

Country of ref document: DE

Date of ref document: 20021024

NLV1 Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act
ET Fr: translation filed
26N No opposition filed

Effective date: 20030619

PGFP Postgrant: annual fees paid to national office

Ref country code: DE

Payment date: 20141211

Year of fee payment: 20

Ref country code: GB

Payment date: 20141219

Year of fee payment: 20

PGFP Postgrant: annual fees paid to national office

Ref country code: FR

Payment date: 20141219

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 69528246

Country of ref document: DE

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Expiry date: 20151221

PG25 Lapsed in a contracting state announced via postgrant inform. from nat. office to epo

Ref country code: GB

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20151221